1. Field
One or more aspects of embodiments of the present disclosure relate to organic light-emitting devices, and more particularly, to an organic light-emitting device that includes a hole transport region including a mixed material.
2. Description of the Related Art
Organic light-emitting devices are self-light emitting devices that emit light when voltage is applied to the device. Organic light-emitting devices provide high luminance, high contrast, multi-color reproduction, and a large viewing angle, and have quick response rate and low driving voltage.
An organic light-emitting device typically has a structure that includes an organic emission layer between an anode and a cathode. When voltage is applied to the device, holes from the anode and electrons from the cathodes are injected into the organic emission layer. The injected holes and electrons induce exchange of electrons between adjacent molecules in the organic emission layer, and then migrate towards opposite electrodes. When the electrons and holes recombine in certain molecules, molecular excitons in a high-energy excited state are generated. When the molecular excitons return to a low-energy ground state, they emit light of a certain color.
When holes and charges (e.g. electrons) injected into the organic emission layer are balanced, the organic light-emitting device may have improved efficiency and improved lifetime characteristics.